var array = [2, 5, 9];

console.log(array);

var index = array.indexOf(5);
if (index > -1) {
array.splice(index, 1);
}

// array = [2, 9]
console.log(array);

var myElement = "chocolate";
var myArray = ['chocolate', 'poptart', 'poptart', 'poptart', 'chocolate', 'poptart', 'poptart', 'chocolate'];

/* Important code */
for (var i = myArray.length – 1; i >= 0; i–) {
if (myArray[i] == myElement) myArray.splice(i, 1);
}